Multi-stage collapse events in the South Soufrière Hills, Montserrat as recorded in marine sediment cores

We present new evidence for sector collapses of the South Soufrière Hills (SSH) edifice, Montserrat during the mid-Pleistocene. High-resolution geophysical data provide evidence for sector collapse, producing an approximately 1 km3 submarine collapse deposit to the south of SSH. Sedimentological and geochemical analyses of submarine deposits sampled by sediment cores suggest that they were formed by large multi-stage flank failures of the subaerial SSH edifice into the sea. This work identifies two distinct geochemical suites within the SSH succession on the basis of trace-element and Pb-isotope compositions. Volcaniclastic turbidites in the cores preserve these chemically heterogeneous rock suites. However, the subaerial chemostratigraphy is reversed within the submarine sediment cores. Sedimentological analysis suggests that the edifice failures produced high-concentration turbidites and that the collapses occurred in multiple stages, with an interval of at least 2 ka between the first and second failure. Detailed field and petrographical observations, coupled with SEM image analysis, shows that the SSH volcanic products preserve a complex record of magmatic activity. This activity consisted of episodic explosive eruptions of andesitic pumice, probably triggered by mafic magmatic pulses and followed by eruptions of poorly vesiculated basaltic scoria, and basaltic lava flows.

The use of a Riesz fractional differential-based approach for texture enhancement in image processing

Texture enhancement is an important component of image processing that finds extensive application in science and engineering. The quality of medical images, quantified using the imaging texture, plays a significant role in the routine diagnosis performed by medical practitioners. Most image texture enhancement is performed using classical integral order differential mask operators. Recently, first order fractional differential operators were used to enhance images. Experimentation with these methods led to the conclusion that fractional differential operators not only maintain the low frequency contour features in the smooth areas of the image, but they also nonlinearly enhance edges and textures corresponding to high frequency image components. However, whilst these methods perform well in particular cases, they are not routinely useful across all applications. To this end, we apply the second order Riesz fractional differential operator to improve upon existing approaches of texture enhancement. Compared with the classical integral order differential mask operators and other first order fractional differential operators, we find that our new algorithms provide higher signal to noise values and superior image quality.

Portrait of Ernst Gottschalk (seated second row center) with eight unidentified soldiers; Rendsburg, Germany. Military Portraits groups

Morgen hat Reserve Ruh / Auf Wiedersehen / Beste Gruesse; postcard signer Gottschalk; addressee: L Nurzinsky, Altona-Othmarschen, Aidikes Str.

Franz Matthiesen outdoors with his second wife Katherina Früh outside of Franz's Carton Hill home; London.

Digital Image

Portrait of the dancing school class of Therese Molling (second row third from right); Germany.

Mille Ottling ran the dancing school. Therese Molling's daughter Liesel (Elizabeth) Gottschalk and brother Hal attended the same school during the mid 1920s

Portrait of Alfred Lichtenstein's second wife Georgette Wegh; New York.

Digital Image

Portrait of Alfred Lichtenstein's second wife Georgette Wegh; Berlin.

Handwritten dedication signed by Georgette Wegh

Writer Clara Michelson (second from left) seated at an outdoor table with three unidentified women and one unidentified man; Saint-Brevin-les-Pins, France Portraits Groups

Digital Image

Portrait of Ernst Gottschalk (seated second row center) with eight unidentified soldiers; Rendsburg, Germany. Military Portraits groups

Morgen hat Reserve Ruh / Auf Wiedersehen / Beste Gruesse; postcard signer Gottschalk; addressee: L Nurzinsky, Altona-Othmarschen, Aidikes Str.

Franz Matthiesen outdoors with his second wife Katherina Früh outside of Franz's Carton Hill home; London.

Digital Image

Portrait of the dancing school class of Therese Molling (second row third from right); Germany.

Mille Ottling ran the dancing school. Therese Molling's daughter Liesel (Elizabeth) Gottschalk and brother Hal attended the same school during the mid 1920s

Portrait of Alfred Lichtenstein's second wife Georgette Wegh; New York.

Digital Image